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4.2 motor build

4.2 motor build
:popcorn:

:chug:
~ JR
 
JB wielded the water jacket holes tonight. I used the eco friendly packing peanuts you can buy at staples. I cleaned up the extra JB wield with a feeler gauge by scraping the excess when it was still wet.
 
While we're all anxious to see the dyno sheet , if it were mine Id like to know exactly what I have in the finished product. Id regear first before the Dyno. Or a before and after if your so inclined?
coldair said:
Yes we are :chug: can't wait myself. Not sure if I should do it before I regear it. :confused:
Click to expand...
 
Maybe I will dyno it before and after just to see what gains it will give me. :D
 
Installed the head tonight started checking the lash for the lifters but ran out of time.
 
Nice seeing how this turns out. I just did this mod on my 85 CJ7 AMC 258 i6 / 4.2l . I used the Mopar kit. Im very happy with it. I went down a similar road you did with the sealing of coolant ports. I absolutely did not want to use JB weld, I wanted plugs. The machinist was hesitant to do it, and I was antsy to get it going and went with JB weld. I've got a few drips, which sucks. Im just dealing with it for now. I dont know what went wrong, I made sure everything was clean before application....I hope yours turns out better than mine did. Theres a bit of a pucker factor on initial start up too when you're trying to get that high idle for initial run in and the idle is choppy and rough at first as the computer settles in.
Good luck on the rest.
 
coldair said:
Installed the head tonight started checking the lash for the lifters but ran out of time.
Click to expand...

:)Looks Good................get it running!
:D:D:D:D
 
coldair said:
JB wielded the water jacket holes tonight. I used the eco friendly packing peanuts you can buy at staples. I cleaned up the extra JB wield with a feeler gauge by scraping the excess when it was still wet.
Click to expand...

:)Cold air...........so I see you plugging up these water jacket holes and I also see others complaining about this process and leaks, whats up with that?
Is there not the correct Gasket available?

I know people that I have used in the racing community that can punch any Custom copper gasket & any thickness with or without holes.
:D:D:D:D
 
tarry99 said:
:)Cold air...........so I see you plugging up these water jacket holes and I also see others complaining about this process and leaks, whats up with that?
Is there not the correct Gasket available?

I know people that I have used in the racing community that can punch any Custom copper gasket & any thickness with or without holes.
:D:D:D:D
Click to expand...
Tarry the stock gasket has no cut outs where i plugged those holes. The block on the AMC 258 i6 / 4.2l dosent have enough there to support the gasket so it weeps. I never thought about an copper gasket though.
 
coldair said:
Tarry the stock gasket has no cut outs where i plugged those holes. The block on the AMC 258 i6 / 4.2l dosent have enough there to support the gasket so it weeps. I never thought about an copper gasket though.
Click to expand...

Coldair,

:)OK I get it now I thought your were doing that to a gasket it looked copper colored in the photo........OK My Bad , I know nothing about these inline 6 cyl's so it really is holes in the Block that are unwanted. I have used a product called Block Rock in the past a epoxy based material that is water & pressure proof.
Anyway Good Job , Carry on!
:D:D:D:D
 
Update I pulled the head off tooK it to a friend that builds race motors he checked the valve springs they will work. Then yesterday I took it to a new machinist to address some issues that have been bugging me. He also checked the springs to make sure they will work with this cam. He assured me they will work great. :D Everything will be back on track and motor will be ready to drop in after I reinstall the head next week :banana::D
 
Nice , cant wait to see the results. :drool:
coldair said:
Update I pulled the head off tooK it to a friend that builds race motors he checked the valve springs they will work. Then yesterday I took it to a new machinist to address some issues that have been bugging me. He also checked the springs to make sure they will work with this cam. He assured me they will work great. :D Everything will be back on track and motor will be ready to drop in after I reinstall the head next week :banana::D
Click to expand...
 
I finally found the time to read your whole thread. Great work! As long as you cleaned the crud out the extra water jacket ports and pushed the peanuts in deep enough, the JB Weld should work just fine. Mine hasn't leaked a drop in 25 thousand miles. Now I'm deciding whether to dig it all back out when I put it on the 4.0 block that I'm building. The stock gasket has no holes, so I really don't see a need to open them back up. :D

What Comp cam grind number did you go with? Or did I miss that in one of your posts? I decided on the 252h for the stoker I'm building because it only increases the valve lift to .433" from the stock 95 H.O. 4.0 cam's .424", so my stock 95 springs should be fine. Which 4.0 head casting number are you running again?

Can't wait to see those dyno numbers! I didn't get mine dynoed when I did the head swap, but seat of the pants tells a lot, and I promise you'll be really happy with all the extra power, and gas mileage to boot! :chug:
 
i haven't been able to find any company that makes an aftermarket hydraulic roller setup for the AMC 258 i6 / 4.2l /4.0 motors, why is that? being from the chevy/ford V8 world, this is the bread and butter of a motor build and i can't seem to find any info on anyone doing a roller setup in the AMC 258 i6 / 4.2l /4.0.
 
With the cam, lifter, valve springs, retainers, locks, hardened pushrods I payed $632.00
 
coldair said:
These guys build roller cams forthe 4.0 pretty sure you could put one in a AMC 258 i6 / 4.2l but at $1200 im ok with what i have. Hydralic roller cam jeep 4.0 stage 2 - 505performance
Click to expand...

thats actually not an "out of this world" price for the entire setup. would have to get roller rockers on top of that as well, but the performance and reliability you gain with a roller setup is unmatched. eliminates so much stress on your valvetrain. i think if i were to ever HAVE to pull my motor and rebuild it, i would be strongly inclined to go this route. it's the best of both worlds, highest performance off road, most reliable in day to day driving. a flat tappet cam with the same specs would drive/idle much worse.

just realized i sound like a salesman. sorry, just my 2 cents on valvetrain.
 
justinfonder said:
thats actually not an "out of this world" price for the entire setup. would have to get roller rockers on top of that as well, but the performance and reliability you gain with a roller setup is unmatched. eliminates so much stress on your valvetrain. i think if i were to ever HAVE to pull my motor and rebuild it, i would be strongly inclined to go this route. it's the best of both worlds, highest performance off road, most reliable in day to day driving. a flat tappet cam with the same specs would drive/idle much worse.

just realized i sound like a salesman. sorry, just my 2 cents on valvetrain.
Click to expand...

:)That might be a great Cam and roller setup if you operate your engine in that RPM range and have the induction & Ignition system to go along with it....... ..................1500-5500 RPM's so and average of 3000 RPM's to see any gain???
:D:D:D:D
 
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